What is "paractinoceras"

Paractinoceras is a long straight slender actinocerid ammonite with siphuncular segments in the early stages like those of Actinoceras, becoming narrower in the later stages of the chambered phragmocone like those in Ormoceras. As with Kochoceras and Floweroceras Paractinoceras is considered a separate genus within the Actinoceratidae, distinct from Actinoceras.